1. Field of the Invention
This invention relates generally to electronic networks, and relates more particularly to a system and method for fast data transfers in an electronic network.
2. Description of the Background Art
Implementing an effective method for managing communications between electronic devices within an electronic network is a significant consideration of designers, manufacturers, and users of electronic devices. An electronic device in an electronic network may advantageously communicate with other electronic devices in the network to share data and substantially increase the resources available to individual devices in the network. For example, an electronic network may be implemented in a user""s home to enable flexible and beneficial sharing of resources between various consumer electronic devices, such as personal computers, digital video disc (DVD) devices, digital set-top boxes for digital broadcasting, television sets, and audio playback systems.
In some types of electronic networks, electronic devices may be xe2x80x9cdaisy-chained,xe2x80x9d so that devices are directly connected to one another in a tree-like structure instead of being connected to a common network bus structure. In such a network, data being delivered via the bus may pass through various intermediate devices before arriving at the destination device. Each device in the chain preferably processes data without undue delay so that data transfers across the network are as efficient as possible.
One type of data transfer that may occur in an electronic network is an isochronous data transfer. Isochronous data transfers are typically used for time-sensitive applications. Video or audio data being transmitted across a network needs to arrive at a display device in an uninterrupted flow with appropriate timing. Isochronous data transfers allow data to be delivered as fast as it is displayed to facilitate the synchronization of audio and video data. For example, an analog voice signal may be digitized at a rate of one byte every 125 microseconds. It is advantageous to deliver this voice data at a rate of one byte every 125 microseconds for the display device to correctly reconstruct the analog voice signal.
Since timing is significant for effective isochronous data transfers, processing isochronous data should be as efficient as possible for timely delivery of the isochronous data. Therefore, managing communications between electronic devices in an electronic network remains a significant consideration for designers, manufacturers, and users of electronic devices.
In accordance with the present invention, a system and method are disclosed for implementing fast data transfers in an electronic network. In one embodiment, the invention includes a data transfer engine configured to independently execute data transfer instructions, and a processor configured to forward the data transfer instructions to the data transfer engine. The data transfer engine preferably executes the data transfer instructions while the processor proceeds to execute a next instruction. The data transfer instructions include move-multiple instructions for moving words of data from one device to another. The data transfer instructions include transmit transfer instructions and receive transfer instructions, which may be differentiated by the designation of a source register and a destination register in the move-multiple instructions.
The data transfer engine includes a transmit engine that executes the transmit transfer instructions, and a receive engine that executes the receive transfer instructions. The transmit engine and the receive engine operate independently and thus may operate concurrently, while the processor advantageously may execute next instructions. The transmit engine and the receive engine preferably execute the move-multiple instructions so that there are no delays between adjacent words of data. In other words, the data is preferably delivered to a destination device at a rate of one word per clock cycle.
The data transfer engine also preferably includes an instruction decoder that receives the data transfer instructions from the processor. The instruction decoder sends the transmit transfer instructions to the transmit engine, and sends the receive transfer instructions to the receive engine. The data transfer engine also preferably includes an operation arbiter configured to control independent operations of the transmit engine and the receive engine. The present invention thus efficiently and effectively implements a system and method for fast data transfers in an electronic network.